LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Volkswagen >> 2011 >> Eos Lux, 2.0 W >> Repair and Diagnosis >> Engine Performance >> Ignition System >> 2.0L - Generic Scan Tool - Engine Code(S): CBFA >> St Generic Scan Tool >> Diagnosis And Testing >> Diagnostic Procedures >> Oxygen Sensor Regulation In Center Three Way Catalytic Converter, Checking
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Oxygen Sensor Regulation In Center Three Way Catalytic Converter, Checking

NOTE:

Use only gold-plated terminals when servicing terminals in the electrical harness connectors of the Oxygen Sensor (O2S) 2 in center Three Way Catalytic Converter (TWC) -G108-.

Special tools and workshop equipment required 

Test requirements 

Test procedure 

-- Perform a preliminary check to verify the customers complaint. Refer to PRELIMINARY CHECK .

Start diagnosis 

-- Perform the function test in Diagnostic Mode 06.

If specified values are obtained:

-- Check for possible intermittent connection or rub through of harness.

If the specified value was Not obtained:

Checking primary voltage 

-- Disconnect the Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) -G108- electrical harness connector.

Fig 1: Identifying Right Vehicle Floor Cover
GWWA10-1663Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Switch the ignition On.

-- Using a multimeter, check the Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) -G108- electrical harness connector terminals 3 to 4 for voltage.

Fig 2: 4-Pin Electrical Harness Connector & Terminals
GWWN24-1641Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

Specified value: 0.400 to 0.500 Volts

-- Switch the ignition Off.

If the specified value was obtained:

-- Replace the Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) -G108-.

If the specified value was Not obtained:

Checking wiring 

-- Remove the Engine Control Module (ECM) -J623-.

-- Using a multimeter, check the Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) -G108- electrical harness connector terminals to the Engine Control Module (ECM) -J623- electrical harness connector T94 terminals for resistance.

Fig 3: 4-Pin Electrical Harness Connector & Terminals
GWWN24-1641Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.
Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) -G108- electrical harness connector terminals Engine Control Module (ECM) -J623- electrical connector T94 terminals or test box sockets
3 34
4 62

Specified value: 1.5 Ω Max.

If the specified value was Not obtained:

-- Check the wiring for an open, high resistance, short circuit to each other, voltage, or Ground.

-- Check the electrical harness connector for damage, corrosion, loose or broken terminals.

-- If necessary, repair the faulty wiring connection.

If no malfunction is found in the wiring:

-- Erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .

-- Perform a road test to verify active fault.

If the DTC does not return:

Generate readiness code. Refer to READINESS CODE .

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was OK:

-- Replace the Engine Control Module (ECM) -J623-.

-- Assembly is performed in the reverse of the removal.

Final procedures 

After repair work, the following work steps must be performed in the following sequence:

  1. Check the DTC memory. Refer to DIAGNOSTIC MODE 03 - READ DTC MEMORY .
  2. If necessary, erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
  3. If the DTC memory was erased, generate readiness code. Refer to READINESS CODE .